Method of and apparatus for road construction



May 29, 1934. J N BYRD 1,960,661

METHOD OF AND APPARATUS FOR ROAD CONSTRUCTION Filed Jan. 5. 1951 5 Sheets-Sheet l y 29, 1934- J. N. BYRD 1,960,661

METHOD OF AND APPARATUS FOR ROAD CONSTRUCTION Filed Jan. 6, 1931 3 Sheets-Sheet s 9/7/65 fujiyraf May 29, 1934. 6 N BYRD 1,960,661

METHOD OF AND APPARATUS FOR ROAD CONSTRUCTION Filed Jan. 6, 1931 3 Sheets-Sheet 3 Patented a, 29, 1934 UNITED" STATES PATENT OFFICE METHOD OF AND APPARATUS FOR ROAD CONSTRUCTION Application January 6, 1931, Serial No. 507,009

9 Claims. (Cl.

This invention relates to a method of and apparatus for ,road construction.

In order to thoroughly understand and realize the importance of my invention in the progress of improving road construction, consideration must be given to the present day methods and apparatus, particularly in reference to the bituminous types of roads.

There are most generally used two methods of bituminous road construction, namely the penetration method and the hot mechanical mix method.

The penetration method consists briefly in spreading the desired thickness of cold,-dry' aggregate on a suitable foundation, then compressing the same, after which hot bitumen is sprayed or poured over the aggregate in suflicient quantity to run or leak through the interstices thereof and coat and bind the aggregate. A top finishing may then be applied in the form of smaller sized aggregate and bitumen.

Investigation and analysis of the penetration 'methodhave shown that there exist many disadvantages incident thereto, the basic and most prevalent of which is the failure of the bitumen to entirely seep through the aggregate and to completely coat each fragment thereof. The reason for this is quite obvious. When the hot bitumen is sprayed or poured over the cold aggregate its viscosity becomes more pronounced, even under favorable weather conditions, and if exposed to normal winter temperatures and brought into contact with the cold aggregate, it will approach a solid condition. Under the best circumstances the seepage of the bitumen will not extend entirely through the compressed aggregate and will only coat the portions of the fragments of aggregate abutting the interstices. The results are that the aggregate is not thoroughly subjected to a binding agent and under the stress of traffic and use, it will shift relative to the foundation of the road; Water and freezing weather will cause displacement of the aggregate; and, necessarily, repeated repairs must be made with excessive maintenance charges.

The hot mechanical mix methodconsists briefly in transporting the aggregate to a mixing plant where it first is dried, heated to and maintained at the necessary temperature, then mixed with.

essary amount of labor for operations. Naturally, the use of .the method in question is limited to territories 'where plants of the type described are located and the expenses appertaining thereto are excessive hibitive.

My method of and apparatus for road construction is designed to overcome. the aforementioned disadvantages relative to the two methods of road construction discussed and to offer advantages and results heretofore unknown;

Oneof the objects of my invention is to provide a method of and apparatus for road construction which will so thoroughly commingle the ingredients of a bituminous type of road, namely aggregate and bitumen, that each and every fragment is completely coated from the top of the layer to the very foundation, the ultimate effect being to completely bind the aggregate 7 into a substantially solid mass.

Another object of my invention is to provide a method of and apparatus for road construction which will allow, when mixed with bitumen, the use of a variety of materials as ingredients of abituminous type of road,'such as many kinds ofstone, slag, gravel, shell and the like. This is highly advantageous, particularly in rural districts, since it will be unnecessary to transport the usual. type of aggregate now used to a point of operation where there exists such aforementioned material.

Another object of my invention is to provide a method of and apparatus for road construction which materially reduces the cost of a bituminous type of road, that is, by eliminating approximately more-than one-half of the labor now required and by reducing the amount of ingredients now used. It' has been found that because of the thorough commingling of the ingredients, a better result than now obtained can be had by using Another object of my invention is to provide a method of and apparatus for road construction which will produce a road of a bituminous type, 100

a great deal more quickly per square foot than by any method heretofore used. Actual experiments have proven that where the hot mechanical mix method produces approximately two thousand square yards per day, my invention will 105 produce approximately ten thousand square yards per day.

Another object of my invention is to provide a method of and apparatus for road construction which can operate under all weather conditions, 110

and in the majority of cases pro- 5 particularly in cold weather, and on all kinds of surface conditions, whether the foundation of the road is dirt, rock, shale, or an old macadam, concrete, or bituminous road, as well as gravel or sand.

Still another object of my invention is to provide a method of and apparatus for road construction which will reduce the actual apparatus necessary in building a bituminous type of road, since my apparatus comprises a single machine which continuously performs the several operations simultaneously. The machine, which is simple in construction, is exceedingly sturdy and emcient and the manufacturing cost thereof is exceptionally small.

With these, and other objects and advantages in mind, attention is called to the drawings where there is shown the apparatus used in my method of roadconstruction, and in which:

Figure 1 isa side elevation of the machine.

Figure 2 is a back view of the machine.

Figure 3 is a plan view of the'machine.

Figure 4 is a detailed elevation of one type of mixing blade used.

Figure 5 is a detailed elevation of another type of mixing blade used.

Figure 6 is a detailed elevation of the side blades used.

Figure 7 is a detailed elevation of the series of curved spreading blades used, and

Figure 8 is a diagrammatic view of the arrangement of mixing blades,'spreading blades and the levelling blade.

Referring particularly to the drawings, in which like numerals indicate like parts, a superstructure frame comprises upwardly curved bars 1 and 2, which converge slightly toward their wheel 8. A tongue 9 is secured to the U-shaped axle frame to facilitate attachment to a power propelling means,-such as a tractor. It will be noted that the axle and wheels may be turned beneath the super-structure frame, thereby allowing a comparatively short turning radius for the machine.

The frame 4 is supported by wheels 10, mounted on axle 11, secured thereto, and comprises the side bars 12, front end bar 13, and a rear end bar 14. Cross bars 15 extend between the side bars 12 to addrigidity tothe frame.

Secured on the front end of frame 4, and at each end thereof, is a support 16 having a housing in which are mounted worm gears 17, provided with adjusting wheels 18. Above the worm gear housings are brackets 19 which hold shafts 20 at the ends of which are gear wheels 21, meshingwith said worm wheels. The other'ends of shafts 20 are rotatably held in brackets 22, attached to the sides of the curved bars 1 and 2. Adjacent the brackets 22, the said shafts are bent outwardly, as at 23, and at their ends are'provided with closed hook members 24, in which are suspended the arms 25, said arms movably supporting a blade holding frame. I

Extending from and secured to the king pin 5 is warm 26, and extending from and secured to the lowerside of cross blade 3 is an arm 27 between which there is held a pin 28. .Two bars 30 and 31 converging at their front ends are slidably held by pin 28, and divergeas they extend rearwardly and horizontally as at 32, then obliquely as at 33, and finally horizontally as at 34. At the rearmost ends of said bars are vertically positioned angle bars 35, having apertures therein.

The blade holding frame comprises front end 'member 36, side members 37, which have angle bars 38 with apertures therein vertically positioned at their. rearmost ends, and cross members 39, 40', 41 and 42. To the portions 34 of bars 30 and 31 are secured the cross members 39,

'40, 41 and 42. The arms 25 are attached to the "Fig. 5 is preferable as rearwardly disposed blades.

The blade shown in Fig. 5 comprises a round snub'nose 43' and diverging sides 44, with suitable means, such as plate 45 for attachment to the blade-holding frame. It will be noted that the nose 43' extends above the sides 44, and that said sides are flared at their tops and bottoms to effect a substantially concave surface.

The blade shown in Fig. 4 comprises a, pointed nose 46, which turns slightly upwardly at its base, recedes rearwardly, and curves upwardly, so that the top portion overhangs the center of Y the curved portion of the blade. The sides 47 of the blade diverge rearwardly and are flared at the tops and bottoms thereof to eifect a substantially concave surface. Suitable means, suchas plate 48 and rod 49 are provided for attaching the blade to the blade-holding frame.

The side blade, shown in Fig. 6, comprises a concaved portion 50, having a suitable means, such as a plate 51 for attaching the blade to the blade holding frame.

The front mixing blades shown in Fig. 4, are two in number, and are attached to the bladeholding frame by means of the plates 45 secured to bars 52, which span the frontend member '36 and cross members 39, 40 and 41, and are. attached thereto.

The remaining mixing blades of the type shown in Fig. 5, are six in number, two of which are attached to cross member 40, two of which are attached'to cross member 41,,and two of which are attached to cross member 42 by means of plates 48 and rods 49. the latter elements being secured'to the preceding cross members.

The positioning of the mixing and side blades on the mixing blade holder heretofore described is of the greatest importance. It will be noted that the mixing blades are placed in staggered relationship to each other, and attention is called to Fig. 8, where a diagrammatic view of the positions of the blades is disclosed. The line A-A in Fig. 8, designates a central longitudinal division of the machine.

I Looking from the rear to the front of the machine, the right hand front mixing blade is placed adjacent-and to the right of the line A-A, and the left hand front mixing blade is placed between the left hand side member of the blade 150 holding frame and the line A-A. In the second row the right hand mixing blade is placed between the right hand side member of the blade -holding frame and line A--A, and the left hand mixing blade is placed adjacent and to the left of the line A--A. The relative positions of the third row of mixing blades corresponds to that of the front row of mixing blades, and the fourth row of mixing blades to that of the second row of mixing blades. It will thus be observed that the second'and fourth rows of mixing blades are in staggered relationship to the first and third rows of mixing blades.

The side blades, of which there are four, are attached to the side members of the blade holding frame-and are positioned as follows:

Looking from the rear to the front of the machine, the front right hand side blade is placed between the front end member 36 of the bladeholding frame and cross member 39, and the rear right hand side blade is placed between cross members 40 and '41; the front left hand side blade is placed between cross members 39 and 40, and the rear left hand side blade-is placed between cross members 41 and 42; It will be noted that the side blades are positioned at an angle relative to the longitudinal axis of the machine with their front ends outwardly disposed. The reasons for the position of the blades as described, and the importance thereof, will later be set forth in.detail.

The spreading blades shown in detail in Fig. 7, arev adjustably positioned at the rear of the blade-holding frame, and comprise three curved blades 53, 54 and 55, which aresecured to-the bar 56, upon which are mounted vertically positioned angle bars 57, having apertures therein.

The angle bars 57 coincide with the angle bars 38 vertically disposed at the rearmost ends of the blade-holding frame side ,members 37 and thehand side of the'machine, looking from the rear to the front thereof, and extends from a point such an arrangement of spreading blades will be later discussed in detail.

The leveling blade is positioned beneath the frame 4 and behind the wheels 16. It comprises aportion 53 to which is secured, in any suitable .manner, a curved portion 59, and extends transversely of the machine slightly beyond the width of the rear wheels and the mixing blade holding frame.

A plate 60 is able manner, such as 'a rod 61, loosely positioned in a plate 62 attached to the axle 11, and secured at its rear end to a bar 63. Underneath said plate and at both sides thereof there are provided slightly curved guides 64, against which the top of the leveling blade rests. A brace 65 is centrally positioned on top of plate 60, and through said brace and plate extends the bolt 66, to which is pivoted the leveling blade. The bar 63 is supheld at its front end in any suitported by adjusting rods 67, which are screw threaded and are held in sleeves 68. Adjusting wheels 69 cooperate with the rods 67 to lift or lower the leveling blade. the vertical adjustment of the leveling blade may be provided, such as arms 70, secured to the bar 63 at 71, and extend through the side bars 12, where they are supported by sleeves 72. The said arms are screw threaded and are provided with wheels 73 which, when tightly screwed against the sleeves 72, prevent vertical movement of the adjusting rods 67.

Pivotally held adjacent the top of the leveling blade and at both sides thereof are bars 74, which extend forwardly through slots in plates 75, at- I tached to the axle 11. The said bars are provided with holes 76 to accommodate 'pins 77. Braces 78, secured underneath the bars 74, are attached to the lower part of portion 58 of .the leveling blade.

It will be observed that by means of the bars 74 the leveling blade may be adjustably positioned transversely of the machine, as required.

Before explaining the operation of the machine in conjunction with my method of road construc- -A locking means for tion, attention is called-to, the fact that there are many and various changes and substitutions which can be made and are contemplated relative to the detailed structure of the machine, and within the scope of the invention.

My method of road construction in which the apparatus above described is utilized, involves and consists of laying on the foundation of the road' or upon the surface of an old worn out macadam or bituminous road the desired amount of aggregate over which a predetermined amount of comparatively cold bitumen is spread. The machine is then propelled over the road and the aggregate and bitumen is thoroughly mixed in situ, spread Q evenly over the road surface, and levelled properly from thesides to the crown of the road. Stone, chips, or smaller aggregate may then be spread over the thoroughly mixed aggregate and bitumen to fill up the voidsv therein, after which compression is applied to the road. A final seal coat of bitumen and fine aggregate may be laid, and the road is opened to trafiic.

The term aggregate is used to include'the various types of stone, slag, gravel, shell, and the like, which may be used, and the amount which is laid on the foundation of the road depends, of

course, on external conditions, such as the trafic burden, grade, weather conditions ofthe particit is not necessary that the aggregate or bitumen when applied be hot or in a heated state, as is the case where the usual method of bituminous road building is used.

The thorough commingling in situ of the aggregate and bitumen is accomplished by the mixing blades of the machine and their particular staggered arrangement.

Attention is directed to Figure 3 and the diagrammatic drawing in Figure 8. The first and as it moves forwardly, and consequently away blade holdingframe is lowered to the depth of the aggregate by means of the adjusting wheels 18. As the machine starts, the rounded noses of the front mixing blades will be forced into the aggregate and bitumen to a point approximately scrap-- ing the road foundation. The diverging and concaved sides of the front blades will pick up the aggregate and bitumen adjacent thereto. turn it over, and deposit it directly in front of the noses of the mixing blades following so that the displacement of the aggregate and bitumen from where originally deposited is comparatively slight. The tendency of the front mixing blades, due to their positions relative to the road, is to cause rounded noses of the front blades but force the the slight displacement to be toward the road crown and away from the road curb or side. second row of mixing blades, with their slightly upturned and receding noses, will penetratethe turned over aggregate and bitumen and due to the concaved and diverging sides thereof, the material is again turned over. The process is repeated as described by each row of blades. In order that the second, third, and fourth rows of mixing blades will not dig into the foundation, the lower portion of the noses are slightly turned up as shown in Figure 4. The receding portion of the noses of these blades ,do not lift the aggregate and bitumen to the extent caused by the material rearwardly and bring about a.quicker turning thereof. p

The effect of the turning of the material by each blade is in reality a churning and violent agitation of the aggregate and bitumen with only slight displacement so that the ingredients are so thoroughly commingled that each fragment of the aggregate is entirely. coated withsuflicient bitumen to cause perfect adhesion between the particles from the very foundation to the surface of the road.

The sideblades are arranged to prevent any material from being forced outside of the path covered by the mixing blades. It will be noted that each side blade is concaved and positioned with its rearrnost end pointing substantially toward the noses of the mixing blades in order that the material turned over by the outer diverging sides of the outside mixing blades will be directed toward the noses of the following mixing blades, and their concaved shape will also cause the aggregate and bitumen to be turned over before coming into contact with the following mixing blades.

' the mixing blades.

" the aggregate.

to evenly spread the material after the mixing operation has been completed. The shape and arrangement of the spreading blades are such as to prevent the material from becoming piled up in any one place and to evenly distribute the aggregate and bitumen.

The large blades 53 and 54 are directly behind the two rearmost mixing blades and receive the agitated material from the diverging sides thereof, while the small blade 55 receives the agitated material from the side blade adjacent thereto. It will be noted that the large blade 53 is adjacent the road curb or side to assure no loss of material in that direction.

The levelling blade positioned at the rear of the machine is vertically. and transversely adjustable relative to the machine. After the mixing and spreading operations have been completed, this blade levels and smooths out the material to the desired thickness of the road. Its vertical adjustment is made to determine the depthof the ag-- gregate and bitumen, and its transverse adjustment is made so that whatever excess material over the desired thickness ein'sts, 'will be spread evenly from the road curb or side to the road crown. The ends of the levelling blade extend beyond the rear wheels so that any depression made thereby will be filled up and levelled off.

The operator of the machine stands upon the platform andaby means of theadjusting wheels controlling the mixing blade holding frame and levelling blade, .has complete control over the various adjustmenta The machine shown is constructed to be pro-' pelled by means of a tractor'or truck, but it is is possible to provide the machine, of course, '.with propelling means attached to the rear wheels, which could be ribbedfor traction, such as a motor.

The method of road construction and the ma-- chine used therewith is continuous in that the various operations, such as thorough commingling of the ingredients by churning and violent agitation, is followed immediately by the spreading principle as my machine and do not accomplish the thorough commingling of the ingredients in situ with comparative slight displacement there- It is obvious that there are various modifications and'changes which may be made in the method and in the structure of the machine without departing from the spirit and scope of the appended claims.

I claim:

1. In a machine for road construction, a mobile supporting frame, a second framesuspended therefrom, a plurality of rows of blades secured to said secondframe, said rows extending longitudinally of the machine in staggered rela tionship to each other'to deflect and simultaneously rotate the materials of which the road is to be built back and forth in a. state of constant agitation with relatively slight displacementof the materials between lines bisectfng the said rows of mixing blades.

2. In a machine'for road construction, a mobile supporting frame, a second frame suspended therefrom, a plurality of rows of substantially angular mixing blades secured to said second frame, said rows extending longitudinally of the machine in staggered relationshipto each other to deflect and simultaneously rotate the materials of which the road is to be built back and forth in a state of constant agitation with relatively slight displacement of the materials between lines' ing diverging and concaved sides to deflect and rotate road material secured in staggered relationship to said second frame, means to keep the material .within the path of advance, adjustable means secured to said second frame to spread the material to an even depth, and adjustable means secured to said supporting frame to level the material to the desired thickness.

5. In a machine for road construction, a mobile supporting frame, a second frame adjustably suspended therefrom, a series of mixing blades seing diverging and concaved sides secured thereto at points longitudinally and transversely staggered relative to said second frame, concaved side blades secured to said second frame to keep material of which the road is to be built within the path of advance and impart a rotary movement thereto, curved spreading blades adjustably secured to said second frame, and a blade secured to'said supporting frame to level the material to the desired thickness.

'7. In a machine for road construction, a mobile supporting frame, a second frame adjustably suspended therefrom, a series of mixing blades having diverging and concaved sides secured thereto at points longitudinally andtransversely staggered relative to said second frame, concaved side blades secured to said second frame to keep material of which the road is to be built within the path of advance and impart a rotary movement thereto, curved spreading blades adjustably secured to said second frame, and a vertically and transversely adjustable blade secured to said supporting frame to level the material to the desired thickness.

8. In combination with a mixing blade holding frame for road construction machines, a plurality of longitudinally extending rows of mixing blades arranged at staggered points thereon, said blades being constructed to deflect back and forth in constant agitation and simultaneously rotate the material of which the road is to be constructed.

9. In combination with-a mixing blade holding frame for road construction machines, a series of annular mixing blades arranged thereon, the sides of said blades diverging. rearwardly and being concaved to deflect back and forth in constant agitation and simultaneously rotate the material of which the road is to be constructed.

JAMES NORMAN BYRD. 

